The 4m3 of cedar boards, which form a 12m high circular “funnel”, were treated with Arch Timber Protection’s Dricon fire retardant.

BCL Timber Projects worked closely with architects Richard Rogers Partnership in the project’s specification.

“It was necessary for the timber lining to the dramatic 12m high funnel construction to be impregnation- treated to conform to the required fire regulations,” said BCL’s Mike Adams.

Dricon was also specified for its ability to leave the timber looking natural after the treatment process.